I do not permit my rooster to force himself on any unwilling hen, and yes, I was able to train him, not only not to rape, but also that aggression toward other chickens or humans is not acceptable.
How? I used a chicken leash after the rooster began bullying the hens and pullets. The final straw was when my son and I watched him chase a pullet all around the yard. When he finally did catch her,and mounted her, he pecked her and tore her comb before getting off, then pecked the base of her tail as she did the post-coital fluff, and pulled out one of her tail feathers. The poor pullet ran to us for comfort, and my son said that the rooster didn't how to behave right to females. We treated her ripped comb, and the gash under her wing, and let her rest in my son's lap until she felt well enough to go back to foraging with the other pullets.
I caught Pohaku-Head(the rooster), and put him in his own isolation coop. I talked to one of my friends, who used to be into cockfighting(but left after being busted once too often), and he suggested tying out Pohaku-Head, and gave me a leather leg harness to which I attached a long leash. Now when the chickens are let out for free range time, Pohaku-Head gets leashed outside too and can join the hens foraging, but if he tries to mate them, and they don't want it, they can easily get away. Pohaku-Head learned that if he wants to mate, he needs to respect them and call them over for food or doing the dance which he started doing when they stopped falling for his Tic-tic-tic call to eat(9 times out of 10, when we throw him scratch, he eats it all silently, then calls the hens once it's all gone). Now if he wants action, he needs to dance or call them nicely.
Over the past few days we tried letting him out with the hens without the leash, and he dances or calls them over, so he's trained for the moment. Any sign of hen rape or other aggression, and the leash goes back on.